Friction dampened railway truck bolster

ABSTRACT

In dampened railway car trucks wherein friction shoes are operatively carried in wedge-shaped pockets located at opposite sides of the bolster the invention provides for the retention of the friction shoes in a pocket in the bolster in the event the control springs become damaged or broken. The friction shoes are retained in the bolster pocket by the cooperation of a lip on the lower interior surface of the bolster pocket which engages the leading edge of the wedge-shaped friction shoe and the engagement of the rear vertical surface of the shoe and the adjacent vertical column of the side frame.

United States Patent [191 Korpics Apr.9,1974

[75] Inventor:

[54 FRICTION DAMPENED RAILWAY TRUCK BOLSTER Frank Joseph Korpics, Streamwoocl, Ill.

[73] Assignee: Amsted Industries Incorporated,

Chicago, 111.

[22] Filed: June 22, 1972 121] App]. N0.: 265,396

[52] US. Cl. 105/197 DB, 1 05/206, 105/207 [51] Int. Cl. B6lf 5/06, B6lf 5/12, F16f1/O6 [58] Field of Search 105/197 D, 197 DB, 207, 105/206 [56] References Cited UNITED STATES PATENTS 2,550,910 5/1951 Christenson 105/197 D 2,257,109 9/1941 Davidson Shafer 105/197 D 2,485,104 10/1949 Maatman 105/197 D 2,827,987 3/1958 Williams i 105/197 D 2,176,909 10/1939 Lazna 105/197 D Primary Examiner-Gerald M. Forlenza Assistant Examinerl-1oward Beltran [5 7] ABSTRACT In dampened railway car trucks wherein friction shoes are operatively carried in wedge-shaped pockets located at opposite sides of the bolster the invention provides for the retention of the friction shoes in a pocket in the bolster in the event the control springs become damaged or broken. The friction shoes are retained in the bolster pocket by the cooperation of a lip on the lower interior surface of the bolster pocket which engages the leading edge of the wedge-shaped friction shoe and the engagement of the rear vertical surface of the shoe and the adjacent vertical column 7 of the side frame.

6 Claims, 7 Drawing Figures railway car trucks and more particularly to a particular configuration wherein friction shoes are operatively carried in pockets located at opposite sides of the bolster. Each friction shoe is resiliently mounted on a control spring that urges the friction shoe against a wear plate mounted on the upper portion of the adjacent side frame column. However, novel means are provided for retaining the friction shoe in said pocket independently of the control spring.

It is therefore a primary object of the present invention to provide, in a snubbed truck, a friction shoe which is effectively retained in the bolster pocket and prevented from disengagement independent of the control spring. Thus, in the event of damage or breakage of the control spring the friction shoe is prevented from falling free of the bolster pocket and effectively prevented from causing damage to either the bolster or the bolster supporting springs as commonly occurred in prior art arrangements.-

Another object of the invention resides in the provision of such shoe retaining feature while still allowing for the easy and relatively simple assembly procedure wherein the friction shoe may be pivoted into and out of the bolster pocket when the bolster is in the lowered position between the wider portion of the bolster opening defined by the spaced columns. After raising the bolster into its upperor normal position between the narrower portion of the bolster opening defined by the spaced columns, the bolster support springs may then be inserted between the lower surface of the bolster and the tension memberof the side frame of the railway car truck. At this point each friction shoe is retained in its bolster pocket by the cooperation of lips on the lower interior surface of the bolster at oppositesides of its pocket, which engage the leading edge of the wedgeshaped-friction shoe, and by the engagement of the rear vertical surface of the wedge-shaped friction shoe with the related vertical surface on the upper portion of the adjacent vertical side frame column. Thus it may be seen that even in the absence of the control springs, not

yet positioned, the wedge-shaped friction shoe is prevented from being dislodged from the bolster pocket.

Still another object of this invention is to provide means for retention of a bottom entry shoe in the bolster pocket in the event the control spring associated with that shoe becomes damaged or broken. As a result of this safety feature, a minimum of snubbing action is lost in the event of control spring breakage, inasmuch as the friction shoe previously supported by the broken spring remains in the bolster pocket and thereby prevents the bolster from shifting position laterally thereof as'was common in prior art arrangements. If the bolster were allowed to shift because a friction shoe became disclodged, the opposing shoe on the same end of the bolster would be allowed to ride up in a drastic manner and thereby severely hamper the snubbing action and cause damage to the bolster, side frame and support springsuntil the defective control spring could be replaced.

The invention embodies other novelfeatures, details of construction and arrangement of parts which are hereinafter set forth in the specification and claims and illustrated in the accompanying drawings, forming part thereof, wherein:

FIG. 1 is a fragmentary side view of a railway car truck side frame together with a truck bolster constructed according to the present invention and assembled in their operative position (portions of the side frame and bolster being shown in section to better illustrate the improved constructions).

FIG. 2 is a sectional plan taken along line 2-2 of FIG. 1.

FIG. 3 is a fragmentary side view similar to FIG. 1 showing the bolster lbwered near the bottom of its bolster window to facilitate installation of the friction shoe; one of the friction shoes being shown partially installed.

FIG. 4 is a fragmentary vertical sectional view showing the manner in which the friction shoe is retained in the bolster pocket when the bolster is in the elevated position in the bolster window; retention being maintained in the absence of a control spring.

FIG. 5 is a fragmentary vertical sectional view showing in elevation the friction shoe and associated parts in their operative positions.

FIG. 6 is a perspective view of a friction shoe having retaining lugs on its sides.

FIG. 7 is an exploded isometric view of the truck bol ster and friction shoe illustrating two embodiments of the invention which may be used independently or in conjunction with one another.

Referring now to FIGS. 1 and 2, a portion of a railway truck may be seen which is of conventional construction in that it includes a pair of spaced side frames, one of which 10 is shown. Each side frame has a compression member 12 and a tension member 14 interconnected by spaced vertical columns 16 the sides of which form a window 18 (FIG. 1) substantially rectangular in shape with the upper portion 18a of the window being slightly narrower than the lower portion 18b.

It should be understood that the railway truck for the purpose of the present disclosure may be considered identical at both sides thereof and for the sake of brevity only that portion shown will be described in detail.

The window formed by the compression member 12, tension member 14 and spaced vertical columns 16 is adapted to receive the end of the bolster, generally indicated at 20. The lower surface 22 at the end of the bolster is supported by a plurality of support spring groups 24 (as best seen in FIGS. 2 and 7) which rest at their lower ends on the side frame tension member 14. In opposite side walls 26 at each end of the bolster 20 are wedge-shaped receiving pockets 28 which open outwardly toward the side frame columns 16 and have an inclined inner wall 30 which has a width corresponding substantially to the width of the wedge-shaped friction shoe 32 positioned therein. The inclined inner wall 30 projects above the plane of the bolster to wall 34.

One wedge-shaped friction shoe 32 is operatively carried in each pocket 28 and includes an inclined surface 36 (FIG. 3) corresponding to and frictionally engaging the inclined wall 30 of the pocket 28, as well as a vertical surface 38 for frictionally engaging a vertical wear plate 40 on the adjacent side frame column 16. The lower surface 42 of the wedge-shaped friction shoe is engaged by the upper end of a control spring 44 which is disposed between said friction shoe 32 and the tension member 14 of the side frame 10. The inclined inner wall 30 therefore, provides an inclined thrust area equal to that of the engaged portion of the inclined surface 36 of the wedge-shaped friction shoe 32.

At the lower edge of the inner inclined surface 30 and extending into the pocket 28 is a lip or ledge 46 which is positioned to engage the lower leading edge 48 on the wedge-shaped friction shoe 32.

Thus it may be seen that the contact between the upper portion of the column 16 and the vertical surface 38 of the adjacent friction shoe cooperates with the engagement of the lip or ledge 46 on the lower inside of the wedge-shaped pocket 28 and the lower leading edge 48 of the wedge-shaped friction shoe 32 so as to.

retain the friction shoe 32 in the pocket 28 of the bolster 10, such retention being completely independent of the control spring 44. As long as the bolster remains in the upper portion 18a of the bolster window 18 the friction shoe cannot pivot the required amount to free itself from the pocket 28. Therefore, retention of the friction shoe 32 in the pocket 28 even without the presence of a control spring 44 will prevent the bolster 10 from excessive shifting to the side of the window 18 having the broken control spring 44.

Therefore, one may see that in the event a control spring 44 were to break or become damaged, the friction shoe 32 associated with that control spring 44 could not fall out of the bolster pocket 28 and cause damage to any of the support springs 24 or result in damage to the side frame 10. Also as a result of this safety feature, a minimum of snubbing action is lost in the event of control spring breakage because the retained shoe 32 does not allow the accompanying shoe 32 at the opposite side of the bolster to rise in a drastic manner thus maintaining the end of the bolster substantially in its centered operating position to insure adequate snubbing action while preventing any serious damage to the bolster 20 or support springs 24.

Another embodiment of the invention shown in FIGS. 6 and 7 provides that retention of the friction shoe may also be accomplished by means of a projecting lug 50 on the side wall 52 of the bolster pocket 28 which is disposed in a mating recess or groove 55 in the side wall of the wedge-shaped friction shoe 32. The use of such guide means requires that the shoe be tipped into the bolster pocket 28, guiding the shoe around the retaining lug 50 when the bolster 20 is in the lowered position 18b adjacent the wider spaced portion of the side frame columns 16.

When the bolster 20 is raised to its operating position, adjacent the closer spaced portion 18b of the side frame columns 16, the shoe is restrained by the lug 50 and is unable to traverse the same path as in assembly because the side frame column 16 adjacent the shoe 32 will not allow the shoe 32 to tip sufficiently to accomplish disengagement.

The above result may also be accomplished by providing a projection on the friction shoe, as shown in FIG. 6, with a mating recess (not shown) in the bolster pocket.

One can see that retention of the friction shoe 32 in the bolster pocket 28 can be accomplished by the simultaneous use of either of any of the embodiments described above. That is the use of a projecting lug 50 on the side wall 52 of the bolster pocket 28 which engages guide means 55 on the side of the friction shoe 32 or the reverse arrangement of FIG. 6 wherein lug 54 may be received in a corresponding mating recess in the bolster pocket not shown; this arrangement may be used in conjunction with the ledge or lip 46 on the lower portion of the inclined surface 30 of the bolster pocket 28; thus providing support for the leading edge 48 on the wedge-shaped friction shoe 32. Such an arrange ment affords additional protection against friction shoe dislodgement in the event of control spring 44 damage or breakage.

It is to be understood that I do not wish to be limited by the exact embodiment of the device shown which is merely by way of illustration and limitation as variations and other forms of the device will of course be apparent to those skilled in the art without departing from the spirit of the invention or the scope of the claims. For example, the invention may be utilized in a truck arrangement wherein the wedge pocket is located in the side frame column, and the wedge-shaped friction shoe is urged against a sloping friction surface in the column and against a vertical friction surface on the bolster.

I claim:

1. In a railway car truck, a side frame having spaced columns defining a bolster opening, said columns being relatively widely spaced over a first portion thereof and relatively closely spaced over a second portion thereof, support and control springs on said tension member in said opening, a bolster supported by said support springs and being spaced from said second portion of said columns, friction shoe means supported by said control springs in engagement with said bolster and the adjacent second portion of said columns, and support means on said bolster supporting said friction shoe means against disengagement from said second portion of said columns independently of said control springs, means on said bolster and said first portion of said columns cooperatively allow disengagement of said friction shoe means therefrom when said springs are removed and said bolster and friction shoe means are adjacent said first portion of said columns.

2. The invention according to claim 1 wherein each side of said bolster defines a wedge-shaped pocket with at least one lip extending thereinto, said friction shoe means includes a wedge-shaped friction shoe supported in each pocket and restrained by said lip and said adjacent second portion of said column against said disengagement therefrom independently of said control springs.

3. The invention according to claim 1 wherein said bolster and said friction shoe means comprise cooperative guide means above said support means on the bolster for restraining said friction shoe means against disengagement therefrom.

4. The invention according to claim 3 wherein said guide means comprises a projecting lug on the bolster and a complementary mating recess on said friction shoe means.

5. The invention according to claim 3 wherein said guide means comprises a projecting lug on said friction shoe means and a complementary mating recess on the bolster.

6. In a railway car truck, a side frame having spaced columns defining a bolster opening having a relatively narrow upper portion and a relatively wide lower portion, a bolster defining friction shoe pockets on either side thereof, each of said pockets having at least one shoes being removable from said pockets only when said bolster is adjacent said wide portion of said opening. 

1. In a railway car truck, a side frame having spaced columns defining a bolster opening, said columns being relatively widely spaced over a first portion thereof and relatively closely spaced over a second portion thereof, support and control springs on said tension member in said opening, a bolster supported by said support springs and being spaced from said second portion of said columns, friction shoe means supported by said control springs in engagement with said bolster and the adjacent second portion of said columns, and support means on said bolster supporting said friction shoe means against disengagement from said second portion of said columns independently of said control springs, means on said bolster and said first portion of said columns cooperatively allow disengagement of said friction shoe means therefrom when said springs are removed and said bolster and friction shoe means are adjacent said first portion of said columns.
 2. The invention according to claim 1 wherein each side of said bolster defines a wedge-shaped pocket with at least one lip extending thereinto, said friction shoe means includes a wedge-shaped friction shoe supported in each pocket and restrained by said lip and said adjacent second portion of said column against said disengagement therefrom independently of said control springs.
 3. The invention according to claim 1 wherein said bolster and said friction shoe means comprise cooperative guide means above said support means on the bolster for restraining said friction shoe means against disengagement therefrom.
 4. The invention according to claim 3 wherein said guide means comprises a projecting lug on the bolster and a complementary mating recess on said friction shoe means.
 5. The invention according to claim 3 wherein said guide means comprises a projecting lug on said friction shoe means and a complementary mating recess on the bolster.
 6. In a railway car truck, a side frame having spaced columns defining a bolster opening having a relatively narrow upper portion and a relatively wide lower portion, a bolster defining friction shoe pockets on either side thereof, each of said pockets having at least one integrally cast lip extending therein, said bolster being positioned in said opening, friction shoes positioned in said bolster pockets, said friction shoes being retained in said pockets by said lip when said bolster is adjacent said narrow portion of said opening and said friction shoes being removable from said pockets only when said bolster is adjacent said wide portion of said opening. 